code: def set_testing_headers():
      opener = urllib.request.build_opener()
      opener.addheaders = [("Testing", "True")]
      urllib.request.install_opener(opener)
  
file_path: featuretools/featuretools/tests/demo_tests/test_demo_data.py
imports: import urllib.request
  import pandas
  import pytest
  from featuretools import EntitySet
  from featuretools.demo import load_flight, load_mock_customer, load_retail, load_weather
label_desc: Use image node_id 1 for calling a global function with example usage: set_testing_headers() without return types